666872240 has 20 divisors (see below), whose sum is σ = 1550478144. Its totient is φ = 266748864.

The previous prime is 666872231. The next prime is 666872273. The reversal of 666872240 is 42278666.

It is a tau number, because it is divible by the number of its divisors (20).

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 4167872 + ... + 4168031.

Almost surely, 2^666872240 is an apocalyptic number.

It is an amenable number.

666872240 is an abundant number, since it is smaller than the sum of its proper divisors (883605904).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

666872240 is a wasteful number, since it uses less digits than its factorization.

666872240 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8335916 (or 8335910 counting only the distinct ones).

The product of its (nonzero) digits is 193536, while the sum is 41.

The square root of 666872240 is about 25823.8695783572. The cubic root of 666872240 is about 873.6702479325.

The spelling of 666872240 in words is "six hundred sixty-six million, eight hundred seventy-two thousand, two hundred forty".